rough idle and black smoke what could it be

[methmonster420]

my ranger started running realy bad the other day and now its not driveable it seems to run fine until its idles for about 5 minutes from a cold start then when it warms up it will start to miss when i give it a little bit of gas then it runs fine when i put it halfway to the floor it smells like its running a little rich and when it starts to miss i can see black smoke from the tailpipe and then it will stall out and wont start back up until its been sitting for a couple of hours ive put new plugs wires fuel pump and filter on it and its still doing it what else could it be

 

[mudnsnow]

Your system is way too rich if you see black smoke. A lot of thing can make your system too rich:
bad coolant temperature sensor
bad O2 sensor
fuel pressure too high
bad MAP or MAF sensor.
etc

Each part can be tested to verify their quality. Don't change parts without testing it. And sometime the problem is'nt the sensor but the wiring/connections between the sensor and the CPU

 

[Bob Ayers]

Diaphram ruptured in the fuel pressure regulator.

 

[methmonster420]

Diaphram ruptured in the fuel pressure regulator.

how could i find out if this is the case ill start looking at the connections and try cleaning the maf right now

 

[Bob Ayers]

how could i find out if this is the case ill start looking at the connections and try cleaning the maf right now

If you pull the vacuum line off of it, and raw gas come out, this will verify a ruptured diaphram.

 

[mudnsnow]

best way to check it is to put a fuel pressure gauge on the port on the fuel rail. Mine on my 5.0 doing the same........the pressure was at 70 PSI... replaced the fuel pressure regulator and all was ok.

 

[methmonster420]

If you pull the vacuum line off of it, and raw gas come out, this will verify a ruptured diaphram.

well i checked it and theres no gas coming out and cleaned the maf which wasnt realy that dirty it runs great for the first 10 minutes then all of a sudden its starts to miss and loses power and running rich i can smell it i gotta keep the rpms way up or it will stall and when it does that i cant get it to start back up it tries but it sounds like its running on 2 or 3 cylinders and i gotta keep the peddle to the floor but after it cools down it runs fine like theres nothing even wrong with it until it warms back up so what should i check next just trying one thing at a time

 

[mudnsnow]

look at the temperature sensor, mesure the resistance of the sensor, look on the tech library you will probably find wich resistance you should have at a certain temperature....

 

[pillen140]

could this be the coil overheating? had it happen on a p.o.s mazda of mine, spark was orange. probably not helping but just throwing it out there

 

[methmonster420]

thanks for all the input so far im gonna check the temp sensor tomorrow which im sure is bad because it always stays in the cold range its been this way since ive had the truck also how can i check the coils to see if there overheating i dont think they are there fairly i new replaced them a little over a year ago but its worth looking into

 

[Bob Ayers]

thanks for all the input so far im gonna check the temp sensor tomorrow which im sure is bad because it always stays in the cold range its been this way since ive had the truck also how can i check the coils to see if there overheating i dont think they are there fairly i new replaced them a little over a year ago but its worth looking into

There are 2 different temp sensors, one for yout temp gauge, and one for the PCM. The one for the PCM has a 2-wire connector, the one for your temp gauge has a 1-wire connector.

 

[Hardwareman]

The sensor for the gauge is in the block and the sensor for the PCM is in the thermostat housing tube.





Allen

 

[fireguy12117]

i had a intermittenly faulty MAF on my 2.5 in the beginning of this summer. no CEL but it did pretty much what you described. i checked everything out with the fuel delivery system, convinced it was getting starved and at my wits end, threw a spare 4.0 MAF in and it fired right up and ran like a rapped ape. however, i did have all sorts of coolant temp issues on a 4.0, where the idle was terrible after restarting from being on for 10-15 minutes, like running to the store, coming back out and barely able to get the thing running...

 

[methmonster420]

ok ive found the temp sensor on the hose but cant seem to locate the other one on the engine itself can someone describe what it looks like and which side its on and also ive noticed at night i can see my exhaust manifold glowing is this normal